Question

An object of mass 49 kg at height 14 m is made to fall freely. Calculate the kinetic energy after traveling 9 meters.​

Answer 1

Answer:

2450 J

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Step-by-step explanation:

GIVEN: An object of mass 49 kg at height 14 m is made to fall freely.

TO FIND: The kinetic energy after traveling 9 meters.

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→ Kinetic energy is defined as the energy possessed by an object due to its motion. It is denoted by K.E.

$\huge{\underline{ \green{\boxed{\red{\sf{K.E. \:=\:1/2m {v}^{2}}}}}}}$

(where K.E. is kinetic energy, m is mass and v is velocity)

$\sf\underline{\underline{\green{As\:per\:given\:question}}}$

Initial velocity of an object is zero because initially it is at rest. So, final velocity of an object is 10 m/s. (put time as 1 sec, initial velocity as zero and acceleration as 10 m/s²).

Height of an object from the ground is 14 m, we need to tell it's kinetic energy after travelling 9 m. After travelling 9 m it will be 5 m away from the ground because (14 - 9) is 5 m.

Substitute the values,

$\implies\:\sf{K.E.\:=\:1/2(49)(10)^{2}}$

$\implies\:\sf{K.E.\:=\:1/2(49)(100)}$

$\implies\:\sf{K.E.\:=\:49(50)}$

$\implies\:{\boxed{\sf{\red{K.E.\:=\:2450}}}}$

Therefore, the kinetic energy of an object is 2450J.